suatu ∆abc diketahui panjang sisi ab = 12√2 cm, panjang sisi ac = 4√6cm, dan ∠c = 60°, maka besar ∠b = …………
1. c = 12√2 cm
b = 4√6 cm
∠C = 60°
ditanya ∠B = …?°
^Aturan Sinus ;
b/SinB = c/SinC
Sin B = b/c . SinC
= 4√6 / 12√2 . Sin60°
= 1/3 √3 . 1/2 √3
= 1/6 . 3
Sin B = 1/2
= 30°